Good sign for the economy: More openings will likely lead to more hiring, although it's not always a one-to-one match since some jobs require more skills and experience than what many job seekers have.

Unemployment is now 5.5% in the U.S., down significantly from 6.3% at this point last year.

In another encouraging sign, about 2.7 million people voluntarily quit their jobs in April. They don't typically do that unless they believe there's a better (and often higher paying) job out there they can get quickly.

The number of people quitting their jobs increased in December and has stayed around the 2.7 million level since.

"For those ready to work now, the job openings are clearly there with a skills match being the key needed fit," said Boockvar.